knock knock jokes

I found it amusing to discover that Shakespeare may be the instigator of knock knock jokes. At the very opening of act II, scene III in Macbeth, there is a knocking at the gate. While the porter goes to answer it, he is basically telling knock knock jokes. I went on Wikipedia to see if I could find the origin of knock knock jokes, but it remains unknown. There may be the possibility that they stemmed from Shakespeare's Macbeth. On Wikipedia (if it’s to be trusted), it gives the meaning of each of the porter’s satires for each knock knock joke he makes. Apparently, he is imagining that he is the porter to the gates of hell and is welcoming people in through the gates. Each joke is made in reference to people of various occupations. I just thought that it was interesting how Shakespeare more or less uses the same types of jokes that we have today.